Azure API Management

Introduction

Azure API Management is a fully managed service that enables organizations to publish, secure, transform, maintain, and monitor APIs. In this tutorial, we will cover how to set up and use Azure API Management with .NET applications.

Prerequisites

• An active Azure subscription
• Visual Studio installed with .NET development workload
• Basic knowledge of .NET and RESTful APIs

Setting Up Azure API Management

To set up Azure API Management, follow these steps:

1. Log in to the Azure Portal.
2. Click "Create a resource" and search for "API Management".
3. Select "API Management" and click "Create".
4. Fill in the necessary details such as name, resource group, and location.
5. Click "Review + create" and then "Create" to provision the API Management instance.

Creating a .NET API

Create a new .NET Web API project in Visual Studio:

1. Open Visual Studio and click "Create a new project".
2. Select "ASP.NET Core Web API" and click "Next".
3. Set the name and location for your project and click "Create".
4. Choose the target framework (.NET 6) and click "Create".

using Microsoft.AspNetCore.Mvc;

namespace MyApi.Controllers
{
    [Route("api/[controller]")]
    [ApiController]
    public class ValuesController : ControllerBase
    {
        [HttpGet]
        public IActionResult Get()
        {
            return Ok(new string[] { "value1", "value2" });
        }
    }
}

Publishing the API to Azure

To publish your API to Azure, follow these steps:

1. Right-click on your project in the Solution Explorer and select "Publish".
2. Choose "Azure" as the target and click "Next".
3. Select "Azure App Service (Windows)" and click "Next".
4. Sign in to your Azure account if prompted, and choose your subscription.
5. Select an existing App Service or create a new one, then click "Next".
6. Review the settings and click "Finish".
7. Click "Publish" to deploy your API to Azure.

Configuring Azure API Management

Once your API is deployed, configure it in Azure API Management:

1. Navigate to your API Management instance in the Azure Portal.
2. Click on "APIs" in the left-hand menu and select "Add API".
3. Select "OpenAPI" and provide the URL of your API's Swagger endpoint (e.g., https://{your-api}.azurewebsites.net/swagger/v1/swagger.json).
4. Fill in the necessary details and click "Create".

Testing the API

To test your API, follow these steps:

1. Navigate to the "APIs" section in your API Management instance.
2. Select your API and click on the "Design" tab.
3. Expand the GET operation and click "Test".
4. Click "Send" to test the API endpoint. You should see the response from your API.

Adding Policies

Azure API Management allows you to add policies to APIs for various purposes such as security, transformation, and caching. For example, to add a rate limit policy:

1. Navigate to the "Design" tab of your API in API Management.
2. Click on "All operations" and then "Inbound processing".
3. Click "Add policy" and select "Rate limit by key".
4. Configure the rate limit settings (e.g., calls per minute) and click "Save".

Conclusion

Azure API Management provides a powerful platform for managing and securing APIs. By following this tutorial, you should be able to set up API Management, create and deploy a .NET API, and configure various policies to enhance your API's functionality. Happy coding!